[Bug middle-end/34969] [4.3 regression] ICE with -fipa-cp -ffast-math

["jakub at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>]

------- Comment #2 from jakub at gcc dot gnu dot org  2008-01-28 09:52 -------
Fix:
2008-01-28  Jakub Jelinek  <jakub@redhat.com>

        PR middle-end/34969
        * tree-inline.c (fold_marked_statements): Update resp. remove
        cgraph edges if a call statement has been folded.
        * cgraphunit.c (verify_cgraph_node): Set cfun to this_cfun for
        debug_generic_stmt calls, reset it back afterwards.

        * gcc.dg/pr34969.c: New test.

--- gcc/tree-inline.c.jj        2008-01-22 15:03:23.000000000 +0100
+++ gcc/tree-inline.c   2008-01-28 10:43:17.000000000 +0100
@@ -2936,9 +2936,48 @@ fold_marked_statements (int first, struc
          if (pointer_set_contains (statements, bsi_stmt (bsi)))
            {
              tree old_stmt = bsi_stmt (bsi);
+             tree old_call = get_call_expr_in (old_stmt);
+
              if (fold_stmt (bsi_stmt_ptr (bsi)))
                {
                  update_stmt (bsi_stmt (bsi));
+                 if (old_call)
+                   {
+                     /* Update or remove corresponding cgraph edge if
something changed.  */
+                     tree new_stmt = bsi_stmt (bsi);
+                     tree new_call = get_call_expr_in (new_stmt);
+                     struct cgraph_node *node = cgraph_node (cfun->decl);
+
+                     if (old_call != new_call)
+                       {
+                         struct cgraph_edge *e = cgraph_edge (node, old_stmt);
+                         struct cgraph_edge *ne = NULL;
+                         tree new_decl;
+
+                         if (e)
+                           {
+                             if (new_call)
+                               {
+                                 new_decl = get_callee_fndecl (new_call);
+                                 if (new_decl)
+                                   {
+                                     ne = cgraph_create_edge (node,
cgraph_node (new_decl),
+                                                              new_stmt,
e->count, e->frequency,
+                                                              e->loop_nest);
+                                     ne->inline_failed = e->inline_failed;
+                                   }
+                               }
+                             cgraph_remove_edge (e);
+                           }
+                       }
+                     else if (old_stmt != new_stmt)
+                       {
+                         struct cgraph_edge *e = cgraph_edge (node, old_stmt);
+
+                         if (e)
+                           cgraph_set_call_stmt (e, new_stmt);
+                       }
+                   }
                  if (maybe_clean_or_replace_eh_stmt (old_stmt, bsi_stmt
(bsi)))
                     tree_purge_dead_eh_edges (BASIC_BLOCK (first));
                }
--- gcc/cgraphunit.c.jj 2008-01-28 09:30:03.000000000 +0100
+++ gcc/cgraphunit.c    2008-01-28 09:31:03.000000000 +0100
@@ -658,6 +658,7 @@ verify_cgraph_node (struct cgraph_node *
   struct cgraph_edge *e;
   struct cgraph_node *main_clone;
   struct function *this_cfun = DECL_STRUCT_FUNCTION (node->decl);
+  struct function *saved_cfun = cfun;
   basic_block this_block;
   block_stmt_iterator bsi;
   bool error_found = false;
@@ -666,6 +667,8 @@ verify_cgraph_node (struct cgraph_node *
     return;

   timevar_push (TV_CGRAPH_VERIFY);
+  /* debug_generic_stmt needs correct cfun */
+  set_cfun (this_cfun);
   for (e = node->callees; e; e = e->next_callee)
     if (e->aux)
       {
@@ -808,6 +811,7 @@ verify_cgraph_node (struct cgraph_node *
       dump_cgraph_node (stderr, node);
       internal_error ("verify_cgraph_node failed");
     }
+  set_cfun (saved_cfun);
   timevar_pop (TV_CGRAPH_VERIFY);
 }

--- gcc/testsuite/gcc.dg/pr34969.c.jj   2008-01-28 10:45:55.000000000 +0100
+++ gcc/testsuite/gcc.dg/pr34969.c      2008-01-28 10:45:29.000000000 +0100
@@ -0,0 +1,15 @@
+/* PR middle-end/34969 */
+/* { dg-do compile } */
+/* { dg-options "-O -fipa-cp -ffast-math" } */
+
+double
+foo (double x)
+{
+  return x * x;
+}
+
+double
+bar (void)
+{
+  return foo (0);
+}

If any call is folded during ipa-cp, we IMHO have to update cgraph edges,
otherwise cgraph verification afterwards can't succeed.  Honza, does this make
sense or should it be done elsewhere?  Haven't bootstrapped/regtested this yet.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34969